Computational Complexity

The Japanese puzzle sudoku is a classic example of an NP complete problem for which if there were any polynomial time solutions would indicate that P = NP. This paper aims to prove that such a solution exists, however, the polynomial time taken is so impractical as to make it impossible to ideally solve.

Förster resonance energy transfer (FRET) reactions involving ligands and aromatic amino acids can substantially impact the fluorescence properties of a protein-ligand complex, an impact intimately related to the corresponding binding mode. Structural characterization of such binding events in terms of intermolecular distances can be done through the well-known R(-6) distance-dependent Förster rate expression. However, such an interpretation suffers from uncertainties underlying Förster theory in the description of the electronic coupling that promotes FRET, mostly related to the dipole-dipole orientation factor, dielectric screening effects, and deviations from the ideal dipole approximation. Here, we investigate how Förster approximations impact the prediction of energy transfer dynamics in the complex between flurbiprofen (FBP) and human serum albumin (HSA), as well as a model FBP-Trp dyad, in which recent observation of enantioselective fluorescence quenching has been ascribed to...

En los últimos años ha despertado gran interés investigar acerca de la arquitectura evolutiva de Internet o del diseño de borrón y cuenta nueva para las futuras arquitecturas. Es evidente que aunque las arquitecturas de la redes se diseñan desde cero, tienden a evolucionar a medida que cambia su entorno. Esto ha suscitado algunas preguntas clave: ¿Qué hace que una arquitectura de red evolucione? ¿Qué determina la capacidad de una arquitectura de red para evolucionar a medida que cambia su entorno? En este trabajo, se revisan algunas ideas relevantes acerca de la capacidad evolutiva en la biología, y se compara con la evolución de las arquitecturas de redes computacionales. Se examina el papel de la robustez y la modularidad con respecto a la capacidad evolutiva de las redes. También se discuten los núcleos evolutivos y el equilibrio puntuado, dos conceptos importantes que pueden ser relevantes para la llamada osificación de los protocolos básicos de Internet. Finalmente, se examina ...

Clustering governs huge data by organizing similar data objects into groups. Density-based clustering permits composition of data objects on basis of their density distribution. DBSCAN, an illustrious and prominent density-based clustering algorithm gives birth to arbitrary-framed clusters, without requiring preexisting acquaintances on the number of clusters to be produced. The inputs to DBSCAN principal are: dataset required to be mined, radius of neighborhood-Eps (ε), minimum number of points needed to build a cluster (MinPts). DBSCAN clustering desires these two parameters to be given as input manually and automatic detection of these parameters is a very tedious exercise and has a significant influence on clustering result. In this paper, we contemplated a new and efficient density-based clustering algorithm (E-DBSCAN). The consolidated notion of the proposed approach is that it avoids manual intervention of input values. Experimental results demonstrate effectiveness and efficiency of the proposed algorithm on varied domain of datasets.

The block diagonalization (BD) is a linear precoding technique for multi-user multi-input multi-output (MIMO) broadcast channels, which is able to completely eliminate the multi-user interference (MUI), but it is not computationally efficient. In this paper, we propose the block diagonal Jacket matrix decomposition, which is able not only to extend the conventional block diagonal channel decomposition but also to achieve the MIMO broadcast channel capacity. We also prove that the QR algorithm achieves the same sum rate as that of the conventional BD scheme. The complexity analysis shows that our proposal is more efficient than the conventional BD method in terms of the number of the required computation.

Decision feedback equalizers are commonly employed to reduce the error caused by intersymbol interference. Here, an adaptive decision feedback equalizer is presented with a new adaptation algorithm. The algorithm follows a block-based approach of normalized least mean square (NLMS) algorithm with set-membership filtering and achieves a significantly less computational complexity over its conventional NLMS counterpart with set-membership filtering. It is shown in the results that the proposed algorithm yields similar type of bit error rate performance over a reasonable signal to noise ratio in comparison with the latter one.

No sentido de aquilatar a extração dos macro e micronutrientes, com exceção do Cl e Mo, aliada ao crescimento da planta, amostragens de rainha margarida (Callestephus chinensis) foram executadas aos 0, 18, 34, 46, 59 e 77 dias após o transplante. As plantas foram divididas em raiz, caule, folhas, botões florais, flores analisadas para N, R, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. Observou-se que o crescimento da rainha margarida é contínuo, acentuando-se após os 59 dias de transplante. O teor porcentual dos nutrientes aos 34-46 dias, na matéria seca, oscilou em torno de 4,09% - 4,40% para N; 0,44% - 0,46% para P; 1,65% - 3,19% para K; 1,01% - 1,10% para Ca; 0,34% - 0,45% para Mg; 0,42% - 0,43% para S. Para os micronutrientes os valores encontrados, na mesma época, foram em ppm: B - 23-36; Cu - 18-20; Fe - 105-150; Mn - 115-135; Zn - 64-111. Uma planta de rainha-margarida aos 77 dias contem: 2.049,9 mg de N; 212,5 mg de P; 2.496,6 mg de K; 915,7 mg de Ca; 356,6 mg de Mg; 159,1 mg de S; 2.1...

Two algebraic structures with the same universe are called term-equivalent if they have the same clone of term operations. We show that the problem of determining whether two finite algebras of finite similarity type are term-equivalent is complete for deterministic exponential time.

The class FORMULA[s]∘G consists of Boolean functions computable by size- s De Morgan formulas whose leaves are any Boolean functions from a class G. We give lower bounds and (SAT, Learning, and pseudorandom generators ( PRG s )) algorithms for FORMULA[n 1.99 ]∘G, for classes G of functions with low communication complexity . Let R (k) G be the maximum k -party number-on-forehead randomized communication complexity of a function in G. Among other results, we show the following: • The Generalized Inner Product function GIP k n cannot be computed in FORMULA[s]° G on more than 1/2+ε fraction of inputs for s=o(n 2 /k⋅4 k ⋅R (k) (G)⋅log⁡(n/ε)⋅log⁡(1/ε)) 2 ). This significantly extends the lower bounds against bipartite formulas obtained by [62]. As a corollary, we get an average-case lower bound for GIP k n against FORMULA[n 1.99 ]∘PTF k −1 , i.e., sub-quadratic-size De Morgan formulas with degree-k-1) PTF ( polynomial threshold function ) gates at the bottom. Previously, it was open whet...